SN74LVC138ARGYRG4

Overview

The SN74LVC138ARGYRG4 is a 3-line to 8-line decoder and demultiplexer manufactured by Texas Instruments. It belongs to the LVC logic family, designed for low-voltage digital applications. The device features three binary address inputs (A0–A2) and eight active-low outputs (Y0–Y7). Control is managed via two active-low enable inputs (G1A, G1B) and one active-high enable input (G2). When enabled, the selected output is driven low while others remain high. The component operates within a supply voltage range of 1.65 V to 3.6 V and supports an operating temperature range from -40°C to +85°C.

Feature Summary

• Provides decoding or demultiplexing functions with three binary select lines controlling eight distinct outputs.
• Incorporates three independent enable inputs requiring specific logic states to activate the device operation.
• Outputs are actively driven to a low state upon selection, maintaining high impedance or high state for inactive lines.

Applications

• Address decoding in embedded systems and microcontroller-based designs
• Demultiplexing data streams in communication interfaces
• Chip select generation for peripheral memory or I/O devices

Procurement Notes

Verify the complete part number including the suffix 'RGYG4' to ensure correct package type and environmental compliance. Confirm that the required supply voltage aligns with the 1.65 V to 3.6 V operational range. Check for automotive qualification requirements if the application demands AEC-Q100 standards, as this specific variant may differ from standard industrial grades. Ensure ESD protection measures are adequate during handling.

Selection Notes

Select this component when low power consumption and compatibility with 3.3 V logic families are required. The LVC series offers faster switching speeds compared to older LV variants while maintaining lower voltage operation than HC/HCT types. Consider the QFN package constraints regarding thermal dissipation and PCB layout space. Verify that the input voltage levels match the system's logic thresholds to prevent undefined states.

Part Context

This device is part of the broader SN74LVC138A family of decoders and demultiplexers. It shares functional similarities with other 3-to-8 line decoders but is distinguished by its specific low-voltage CMOS technology and packaging configuration. The family includes variants with different packages such as TSSOP and SOIC, catering to diverse board space and assembly requirements.

Replacement Considerations

Direct substitutes include SN74LVC138ARGYR and SN74LVC138ARGYRG4. Alternative packages like SN74LVC138APWR offer identical functionality in a TSSOP format. Cross-reference with SN74AHC138 for higher speed requirements, noting differences in drive strength and voltage tolerance.